The University of Washington Venereal Disease Program Project (AI 12192) was begun June 1, 1974, with these component projects: I. Epidemiology and Pathogenesis of Gonorrhea, II. Genetic Determinants of Virulence in Neisseria Gonorrhoeae, III. Etiology and Therapy of Nongonococcal Urethritis. This is a proposal for competitive renewal of these projects for five years. Ideally, a program project is interdisciplinary, with close collaboration between investigators in different projects, mutual definition of goals, and greater flexibility in reallocation of resources that exists in individual research grants. These three projects are conceptually complementary, and twice monthly joint research seminars have been held since the beginning of the program to foster interdisciplinary communication. The extent to which the individual disciplines and components of this program have complemented each other, such that the whole has been greater than the sum of the parts, are outlined in each project proposal. It has been possible to initiate pilot studies which led to development of new project proposals in two areas. Project IV: Pathogenesis and therapy of Hemophilus vaginitis, included in this program, and a Young Investigator Award for study of genital herpes (Immunology, Prophylaxis and Therapy of Genital Herpes, No. 1-R23-AI14414-01-EDC) has been submitted separately by Dr. Corey, a recent trainee. This program project also draws upon and at times assists several other research activities at the University of Washington which involve C. trachomatis, genital mycoplasmas, immunochemistry of N. gonorrhoeae, and cytomegalovirus. Dr. Eschenbach is supported by the CDC for study of pelvic inflammatory disease. Future research support will also be sought for studies of perinatal C. trachomatis infections and for sexually-transmitted CMV infection.